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Content versus label claims in ephedra-containing dietary supplements
B J Gurley1, S F Gardner, M A Hubbard
1Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock 72205, USA. gurleybillyj@exchange.uams.edu
Ephedra alkaloid content in dietary supplements varies widely and often differs from label claims. Significant inconsistencies were found between product batches, impacting supplement quality and safety.
Area of Science:
- Pharmacology
- Analytical Chemistry
- Herbal Medicine Quality Control
Background:
- Ephedra (ma huang) is used in herbal dietary supplements.
- Ephedra alkaloids are the active compounds in Ephedra.
Purpose of the Study:
- To determine the ephedra alkaloid content in herbal dietary supplements.
- To assess the variability and accuracy of label claims for ephedra alkaloid content.
Main Methods:
- High-performance liquid chromatography (HPLC) was used to quantify ephedra alkaloids.
- Twenty ephedra-containing supplements were analyzed for specific alkaloids: (-)-ephedrine, (+)-pseudoephedrine, (-)-methylephedrine, (-)-norephedrine, and (+)-norpseudoephedrine.
Main Results:
- Ephedra alkaloid content varied significantly among products, ranging from 0.0 to 18.5 mg per unit.
- Significant lot-to-lot variations were observed, with some exceeding 1000% for (-)-methylephedrine.
- (+)-Norpseudoephedrine, a controlled substance, was frequently detected.
- Half of the products showed label claim discrepancies over 20%; one product contained no ephedra alkaloids.
Conclusions:
- Ephedra alkaloid content in supplements is highly variable and inconsistent.
- Label claims for ephedra alkaloid content are often inaccurate.
- Significant variations and discrepancies raise concerns about product quality and safety.
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